Realization of an Optical Thermometer via Structural Confinement and Energy Transfer

Abstract

The influence of temperature on a variety of physiological or chemical processes has generated considerable interest, and recently noninvasive lanthanide-incorporated optical thermometers have been considered as promising candidates for monitoring its changes at different scales. Herein, a novel Bi 3+ -activated Sr 3−x Gd x GaO 4+x F 1−x phosphor with tunable color has been constructed by a cooperative cation−anion substitution strategy with to the replacement of [Sr 2+ −F − ] by [Gd 3+ − O 2− ]. When x = 0, the sample Sr 3 GaO 4 F/Bi 3+ possesses a peak wavelength at 438 nm, and this value will shift to 470 nm if x is equal to 1 (Sr 2 GdGaO 5 /Bi 3+ ). In addition, photoluminescence tuning from blue to red has been realized successfully by an efficient Bi 3+ → Eu 3+ energy migration model in Sr 2.6 Gd 0.4 GaO 4.4 F 0.6 samples. The specific Bi 3+ → Eu 3+ energy transfer has been explained by dipole−dipole interactions derived from a model of the Dexter pathway. Intriguingly, the two dopants (a blue signal from Bi 3+ and a red signal from Eu 3+ ) possess different thermal responses to increasing temperature. Accordingly, the intensity ratio values are sensitive to the temperature changes. The energy level cross relaxation causes the quenching effect of Bi 3+ , and the multi-phonon de-excitation mode leads to the thermal quenching of Eu 3+ . At room temperature (298 K), the determined maximum relative sensitivity (S r ) is 1.27% K −1 . Moreover, the absolute sensitivity (S a ) is 0.067 K −1 since the temperature is elevated to 523 K. The collected results are superior to most of the reported optical thermometry materials.

Efficient Ce3+ → Tb3+ energy transfer pairs with thermal stability and internal quantum efficiency close to unity

“…Since the exchange interaction comes into effect only when the R c < 5 Å, the electric multipolar interaction might take the largest probability for the mechanism of the Ce 3+ → Tb 3+ ET process. 42,43 To determine which multipole–multipole interaction type governs the process of ET from Ce 3+ to Tb 3+ , the ET expressions for multipolar interaction are used, as proposed by Dexter's theory and Reisfeld's approximation: 44,45 where I S and I 0 are defined as described above in eqn (4), C denotes the dopant concentration, and n = 6, 8, and 10 represent different types of multipole-multipole interactions, corresponding to dipole–dipole, dipole–quadruple, and quadruple–quadruple interactions. Fig.…”

“…Since the exchange interaction comes into effect only when the R c < 5 Å, the electric multipolar interaction might take the largest probability for the mechanism of the Ce 3+ → Tb 3+ ET process. 42,43 To determine which multipole-multipole interaction type governs the process of ET from Ce 3+ to Tb 3+ , the ET expressions for multipolar interaction are used, as proposed by Dexter's theory and Reisfeld's approximation: 44,45…”

Facile Synthesis of Organic–Inorganic Hybrid Layered Rare‐Earth Hydroxide Nanocone for Multifunctional Drug Delivery System with Fluorescence Probe and Simultaneous Magnetic Resonance Imaging

“…As a result, the maximum energy transfer could reach high up to 40%. The energy transfer process could be identified according to Dexter's energy‐transfer theory and Reitfeld's approximation, given as: [ 43,44 ] $$$$\begin{equation} {I}_{0}/I\propto {C}^{n/3} \end{equation}$$$$where C is the total dopant concentration, I 0 and I are the intensity of ASA emission in the absence and presence of Tb 3+ , n = 6, 8, and 10 stands for electric dipole−dipole, dipole−quadrupole, and quadrupole−quadrupole interactions, respectively. The data of I 0 / I versus C n /3 was plotted in Figure S9b (Supporting Information) and fitted with linear functions.…”

Eu3+ Single-Doped Phosphor with Antithermal Quenching Behavior and Multicolor-Tunable Properties for Luminescence Thermometry

“…As is well known, temperature is a significant physical parameter to evaluate heat and cold. , In recent years, measuring temperature more accurately, conveniently, and at low cost has become a research hotspot. As a general rule, the temperature measurement method contains contact type and non-contact type. , Among them, contact temperature measurement requires adequate contact between the sensor and the measured objects to achieve sufficient heat exchange.…”

“…As is well known, temperature is a significant physical parameter to evaluate heat and cold. 1,2 In recent years, measuring temperature more accurately, conveniently, and at low cost has become a research hotspot. As a general rule, the temperature measurement method contains contact type and non-contact type.…”